International Patent Application No. PCT/AU2005/001621 discloses a vertical axis wind turbine in which the blades are relatively thin. Depending upon the size of the wind turbine, the blades may have a thickness which varies between approximately 1 mm and approximately 200-300 mm. One of the problems of fabricating vertical axis wind turbine blades which are thin is that the blade is not very rigid. There is also a tendency for the blade to flutter or vibrate whilst in use. Since wind turbines can be subjected to very strong winds and thus substantial loads, it is necessary for the blades to be mounted in such a way that they can withstand the loads to which they are subjected.
Preferably the blades are moulded from resin reinforced with carbon fibres or are pressed from sheet aluminium. Furthermore, each surface of the thin blades has an aerodynamic function. Consequently, the blade must be mounted in such a way that the mounting does not itself interfere to any appreciable extent with the aerodynamic performance of the blades.